Resorcylic acid azo dye



United States Patent 3,249,599 RESORCYLIC ACID AZO DYE Ernest M. May, Summit, and Andrew Fono, Montclair, N.J., assignors to Otto B. May, Inc., Newark, N.J., a corporation of New Jersey No Drawing. Filed July 20, 1962, Ser. No. 219,806 Claims. (Cl. 260-196) This invention relates to new dyes; and, more particularly, it is concerned with compounds which are especially suitable for dyeing shaped articles of polypropylene and other thermoplastic resins, such as polyesters, polyacrylics, polyamides and other polyolefins.

In the past, manyclasses of dyes have been applied to shaped articles, such as synthetic fibers, in attempt to dye these articles in a commercially satisfactory way, that is to say, to yield a brilliant dyed product which is fast to light, washing and dry cleaning. However, these classes of dyes have not been entirely suitable since the articles dyed therefrom have had a relative poor fastness to light, washing or dry cleaning, or they have had inadequate brilliance.

An object of the present invention is to obtain dye compositions whch are suitable for dyeing polypropylene and other polyolefins to provide an end product with superior fastness properties and with excellent brilliance and tinctorial value.

Another object of the invention is to obtain dyes which can be used for dyeing other thermoplastic resins, such aspolyesters, polyacrylics, and polyamides to form a dyed article having excellent fastness to light, washing and dry cleaning and having exceptional brilliance.

It is common practice in the textile industry to form composite fabrics containing two or more types of fibers. For example, the composite fabric may be woven of threads containing, in a predetermined pattern, threads of polypropylene, nylon, and/or other fibers, such as polyacrylics, natural fibers, etc. With respect to these composite fabrics, there is an immediate problem of finding a dye which will give a union dyeing. This is a problem and a term which is well-known in the art.

Accordingly, another object of this invention is to produce dyes which will dye simultaneously and satisfactorily mixed fabrics composed of more than one synthetic and/ or wool and silk fibers.

A further object of the present invention is to provide dyes which are fast to washing and severe dry cleaning when applied to shaped articles, particularly fibers containing finely dispersed metallic compounds; more specifically to provide dyes of extraordinary brilliance and tinctorial value.

One of the very diflicult problems that has confronted the industry is, stabilizing polypropylene and other polyolefin fibers against ageing, that is, degradation caused by exposure to air, light, and/or heat. Many types of known stabilizers have been incorporated into the fibers to impart some degree of stability thereto. However, these stabilizers generally are removed by washing and/ or dry cleaning with various solvents, and the fibers lose most or all of their resistance to ageing.

Accordingly, still another object of this invention, is to stabilize shaped articles formed from polypropylene and other polyolefins and preferably simultaneously stabilize and pigment such materials.

Another object is to improve stability and the resistance of these polymers to ageing, particularly after they have been washed, dry cleaned or exposed to other solvents.

Other objects and advantages of the present invention will appear from the following description.

According to the present invention, it has been found that certain monoazo gamma-resorcylic acid compounds confer exceptional brilliance and excellent Washing and dry cleaning stability when they are dyed on thermoplastic shaped articles of polyolefins, particularly polypropylene containing a metal; poly-amides; and polyacrywherein each X is a substituent group attached to the benzene nucleus independently selected from the class consisting of C to C alkyl, cyclo alkyl having up to 6 carbon atoms, nitro, halogen, carbacyl having up to 6 carbon atoms, benzoyl, N-alkyl sulfonamido said alkyl containing 1-5 carbon atoms, N,N-diall y1 sulfonamido each of said alkyls containing 1-5 carbon atoms, alkoxy containing l-4 carbon atoms, trifluoromethyl, cyano, benzoylamino, carboalkoxy containing 1-4 carbon atoms, dialkylamino each of said alkyls containing 1-5 carbon atoms, beta cyano ethyl oxy, beta hydroxy ethy'l oxy, a-lkyl sulfonyl containing 1-4 carbon atoms, hydroxy alkyl sulfonyl containing 1-4 carbon atoms, di (beta hydroxy ethyl) amino, di (beta cyano ethyl)v amino, 2,3- benz-, carbonamido and phenyl; R is a substituent group attached to the benzene nucleus selected from the group consisting of hydrogen and a halogen; and a: is an integer from 1 to 5 inclusive.

The foregoing groups may be substituted with simple subs-tituents recognized in the dyeing art such as methyl, nitro, halogen, methoxy and other lower alkoxy groups (containing 1 to 5 carbon atoms), trifluoromethyl car bonamido, etc.

Preferred monoazo gamma-resorcylic acid compounds are found among those in which the group or groups X include at least one lower alkyl, that is 1 to 4 carbon atoms such as methyl, or such compounds in which the group or groups X include at least one trifluoromethyl group, or at least one halogen (fluorine, chlorine, or bromine), or at least one lower alkoxy group (1 to 4 carbon atoms), or at least one nitro group, or monoazo gamma-resorcylic acid compounds in which the group or groupsX include the 2,3 :benz group, that is naphthaleneazo-gamma-resorcylic acids.

The desirable properties of the compounds described above are realized by reacting them with a metallic compound of aluminum or zinc. The reaction product is generally formed in the shaped articles, such as fibers of polypropylene and other polyolefins, by incorporating initially a metal compound of aluminum or zinc into the polyolefin. This procedure will be described more completely hereafter.

The precise nature and structure of the aforementioned reaction product is not clearly understood. However, it is thought that a chelate ring or linkage may be formed between the metallic cation and the adjacent carboxylic and hydroxyl groups on the gamma-resorcylic acid ring, and this may be responsible for the desirable properties of the formed reaction product. Furthermore, there is no precise stoichiometric ratio between the dye and the metallic compound. This is believed to be due to any one or more of a number of factors. In the first place, the metallic compound may not penetrate into all of the interstices of the dye or vice versa; and, therefore, the reaction may not be complete. In the second place, aluminum and zinc are known to exist in the form of polymers or oligimers; and, therefore, a single dye molecule may account for more than one atom of the metal. The amount of dye used may be sufficient to account for all of the metal present; however, this is not an absolute requirement. For instance, in dyeing shaped articles, such as fibers, it may not be necessary to provide enough dye to react with all of the metal which is finely divided and uniformly distributed throughout the mass. Furthermore, the ratio of fiber to metal is not a critical feature of the invention and a suitable ratio may be readily determined from a given set of circumstances and the desired objectives.

A particularly striking feature of this invention is the stabilizing effect of the monoazo gamma-resorcylic acid compounds on the polypropylene or other polyolefin shaped article, such as a fiber. As stated heretofore, stabilizing such materials has been a very difficult prob lem, particularly since laundering, dry cleaning or exposure to other solvents tend to remove known stabilizers. It'has been surprisingly found in accordance with the present invention that the monoazo gamma-resorcylic acid compounds described above impart stability to the polypropylene or other polyolefin and resist removal by laundering, dry cleaning, etc.

The aforementioned dyes can be prepared by various methods. However, they are generally formed by coupling a substituted aniline through diazotization with gamma-resorcylic acid.

In One embodiment, a shaped article, for example, a synthetic fiber, has a metal incorporated therein before a monoazo gamma-resorcylic acid compound is applied. The synthetic fibers or other shaped article applicable to this invention include polyolefins, polyesters, for example, condensation products of polybasic acids with polyhydric alcohols and Dacron; polyamides, such as nylon; polymers of acrylic acid compounds, such as acrylonitrile; and polymers of vinyl compounds, such as vinyl alcohol, vinyl chloride and styrene. A polyolefin, which is the preferred polymer for a synthetic fiber, includes the following polymers among others: polyethylene, polypropylene, polybutene, poly-3-methyl-butene-l, polypentene, poly-4-methylpentene-1, and polyheptene. The polyolefin, e.g., polypropylene, can be prepared by any known method. A suitable, but not the only method, is disclosed in the Belgian Patent No. 533,362.

Synthetic shaped articles are formed from the aforementioned thermoplastic polymers in accordance with known prior art procedures. A fiber, which is preferred, is defined herein as any fibrous unit, for instance, filament yarns, rovings, mats, staple yarns, sheets, rods, plates, woven fabrics and chopped fibers. The following exemplify specific commercial fibers which can be employed herein: Spun Dacron T-54; Nylon Filament Thread; Cresland T58; Acrilan 1656; and Polypropylene 805 Fiber.

Although synthetic fibers are usually employed, the reaction product between metallic material and gammaresorcylic acid compound is also applicable to natural fibers, for example, wool, animalized cotton and silk. Furthermore, it is also possible to use a combination of any two or more synthetic or natural fibers to form a composite fabric. Union dyeing is provided on the composite fabric by using the monoazo dyes described herein.

The metal, which is incorporated into the fiber, forms a reaction product with the subsequently applied dye composition. metals, and they are utilized as metallic compounds. Organic metal salts, which are preferred, may be employed within the range of .02 to .2% based upon the weight of the fiber. Carboxylic acid metal salts with 6 to 20 carbon atoms, which are suitable for this invention, include aluminum stearate, zinc stearate, aluminum laurate, and the aluminum salt of 2-ethyl hexanoic acid. These salts are intimately dispersed throughout the polymer at any stage prior to its extrusion. An efficient blending apparatus is usually adequate to accomplish this result. After dispersion, the blend may be extruded at the fluid temperature for the polymer, that is, 250

Aluminum and zinc are the preferred to 350 C. for polypropylene. Accordingly, the metal is usually distributed uniformly throughout the fiber, such as, polyolefin fiber, which provides complete penetration of the dye from the dye bath into the fibers. By way of illustration, the incorporation of the metal salt in the polymer may be made by mixing 10 parts of the powder of the salt with parts of the powder of the polymer to an intimate and uniformly dispersed mixture. This mixture may be extruded to form a concentrate Which subsequently is finely divided again and intimately blended with additional polymer to obtain the desired low concentration of metal for extrusionto the shaped product. p

The monoazo gamma-resorcylic acid compounds heretofore described form the basis of an aqueous dye bath into which the fibers are immersed. Since the dyes are insoluble in water, they are dispersed or emulsified in the bath. The concentration of the dye bath can vary over a wide range, depending upon the depth of shade desired. Any known dyeing technique can be employed in this invention. For example, a skein can be simply immersed into the bath at its approximate boiling temperature; or a finished piece, can be dyed by using a jigger. The dye bath can be slightly acidic and the fiber is usually rinsed and dried subsequent to its immersion in the dye bath. Known pressure dyeing techniques which accelerate the entry of the dye into the fiber may also be used. 1

In another embodiment of the present invention, the fiber, such as a synthetic or natural fiber, is not modified with a metallic material. This unmodified fiber is immersed directly into a dye bath andsubsequently rinsed and dried. These steps can beaccomplished by any pro cedure known in the art and can be similar to the procedures described for the above embodiment. For example, the aqueous dye bath suspension can contain a sulfonated oil, soap, sodium lignin sulfonate, or other suitable dispersing agent. Although direct dyeing operations are generally performed'at temperatures of about to 212" F., any suitable temperature can be used, including pressure dyeing and thermofixation techniques. The fiber to be dyed is usually added to the dye bath initially at a relatively low temperature and then a higher temperature is provided for carrying out the actual dyeing operation. The intensity of dyeing is varied by changing the proportion of the weight of dye to the weight of the fiber.

Thus, in accordance with the instant invention monoazo gamma-resorcylic acid compounds have been provided which are suitable dyestufis. Furthermore, these compounds will reactwith metal-modified shaped articles to form a dyed end productwhich has excellent brilliance and tinctorial value and which is also fast to light, dry

cleaning and washing. Similarly, these compounds can be applied directly to dye an unmodified fiber since, for example, nylon, polyester, and acrylic fibers have polar groups which can form a polar linkage with the present dyes to improve the receptivity of the dye and the fastness properties, suchtas light fastness of the dye on the fibers.

In still another embodiment of the invention, the monoazo gamma-resorcylic acid compound described above is reacted with the metallic compound in solution without the necessity of any shaped article such as fiber being present, to form a pigment which can be recovered and used as a pigment in a manner known in the art. The reaction conditions and ratios of reactants in'this embodiment of the invention are substantially the same as those described above for the dyeing of fibers.

The following examples are submitted to illustrate but not to limit this invention. Unless otherwise indicated, all parts and percentages in the specificationare based upon weight.

EXAMPLE I A 3-methylbenzeneazo-gamma-resorcylic acid dyestuff was provided by dissolving 15.4 parts (.1 mol) of (pure basis) gamma-resorcylic acid in 500 parts of water containing 24.6 parts (.3 mol) of sodium acetate and 4 parts .1 mol) of sodium hydroxide.

A separate solution was prepared from 11.7 parts (.1 mol) of m-toluidine and 500 parts of water containing 30 parts of concentrated hydrochloric acid. This solution was cooled to 5 C. with the subsequent addition of 7 parts of sodium nitrite dissolved in 100 parts of water. After stirring for /2 hour and filtering, a clarified diazo second solution was formed.

This second solution was added to the first solution over a period of 2% hours at 25 C. After an additional reaction time of two hours, the dyestutf product therefrom was filtered out, washed neutral and finely dispersed to a 10% aqueous paste.

Fiber grade polypropylene, which was blended intimately and uniformly with 0.080 wt. percent of aluminum monostearate, was used to manufacture 4 /2 denier crimped staple fiber by melt extruding, stretching, crimping and cutting to a 2 in. length. This cut fiber was subsequently carded and spun to produce yarns approximating .10s single (cotton system) count. Convenient sized skeins were then reeled from this yarn.

A sample containing ten grams of skein was provided. This sample was immersed in a 500 cc. dye bath at 120 F. The bath consists of an aqueous dispersion of 0.6 gram of the dry aforementioned dyestutf. Prior to the entry of the yarn, suflicient acetic acid was added to the dye bath to provide a pH of 6.0. The dyeing was accomplished by gradually raising the temperature of the dye bath to its boiling point during a 30 minute period. The skein was frequently turned with a glass stirring rod and the temperature was maintained at 212 F. for a period of one hour. The yarn was then removed from the dye bath and thoroughly rinsed in running water at 160 F. The skein was subsequently scoured by turning it for 30 minutes at 160 F. in a 400 cc. aqueous bath containing /2% of Triton X-100 (iso-octyl-phenyl poly ethoxy ethanol) and /z% of sodium carbonate. A thorough rinse was subsequently performed in running water at 110 F.

The dyed sample was then subjected to the following tests.

(1) Color fastness to dry cleaning-Tentative Test Method 85-1960 (1960 Technical Manual of the American Association of Textile Chemists and Colorists, pages 88-9) amended as follows: the temeprature shall be 115 F.; the time shall be 1 hour; and the amount of perchlorethylene shall be 200 cc.

(2) Color fastness to washing (polypropylene). Tentative Test Method 61-1960, test number III-A (1960 Technical Manual of the American Association of Textile Chemists and Colorists, pages 93-4). In each instance, the dyeings shall rate (for polypropylene) as follows: for color loss, class for staining, class 3 or better.

(3) Color fastness for washing (synthetics).--AATCC tentative test method 611961 T (page 105 c. cit.) with Test III-A being used for polyester and after-chromed nylon and Test II-A for nylon.

(4) Color fastness to light.AATCC Standard Test Method 16-A1960 (page 90 10c. cit.).

(5) Color fastness t0 oxides of nitrogen in the atmosphere (gas fading).Three cycles were used of Standard Test Method 23-1957 (page 98 loc. cit.) or Standard Test Method 7519 56 (page 100 loc. cit.).

(6) Sublimation and heart fastness testsqSublimation and heat fastness tests were run at 265 F. for minutes.

The dyed polypropylene herein had a brilliant gold hue and was extremely fast to washing, dry cleaning, gas fading, sublimation and light.

EXAMPLE II A benzeneazo-S-bromo-gamma-resorcylic acid dyestulf was formed by dispersing 9.0 parts (.035 mol) benzene- EXAMPLE III The compounds indicated in Table I are the dyes described in the previous examples and those dyes which were prepared by comparable procedures with the reactants being varied to form the desired end product. Polypropylene was dyed with each compound as per Example I and the resultant shades are also indicated in Table I. All of the dyed products had good fastness to washing and dry cleaning.

Table I H C O OH A-Ring B-Ring Dye No. Substituents Substit- Shade uents Brilliant Gold.

Brilliant Gclden-Orange.

Brilliant Golden-Yellow.

Brilliant Gold.

Brillliiant Golden-Yellow.

Yellow. Golden-Yellow. Brilliant Gold. Do. Orange. 4-CGH5CONH; Red.

2,5-di-C2H5O.

EXAMPLE IV Dye No. 3 in Table I was prepared by dissolving 11.6 parts (.072 mol) of p-trifluoromethylaniline in parts of water containing 24.7 parts (.21 mol) of concentrated hydrochloric acid. After cooling to 5 C., a solution of 5 parts sodium nitrite and 50 parts water was added thereto. The diazo first solution therefrom after /2 hour reaction time was filtered for clarification.

A separate second solution was formed from 11.2 parts (.072 mol) pure gamma-resorcylic acid and 300 parts water containing 24.6 parts (.3 mol) of sodium acetate. Over a period of one hour, the clarified first solution was added to the second solution at 10 C. The dyestuff therefrom after a further reaction time of two hours was filtered and washed neutral. The filter cake was dispersed to provide a uniform 10% aqueous dyestuff paste.

A Dacron fiber was dyed by providing a bath at F. containing 200 parts water and 1.5 parts of a blend of 67% biphenyl and 33% anionic emulsifier. Ten grams of skein were incorporated for a five to ten minute run. The aforementioned dye, which had been previously pasted and dispersed in 100 parts water, was added and the temperature of the bath was raised to boil for 1 to 1% hours. The following procedures were subsequently employed: rinsing for 5 minutes in a fresh bath heated as rapidly as possible to to 200 F.; dropping without cooling; and scouring at 200 F. for 15 to 20 minutes.

The dyed Dacron fiber was a bright gold and it was fast to washing, dry cleaning and light.

Good fastness properties were also obtained by dyeing Dacron to a gold hue with Dye No. 7 (Table 1).

Having set forth the general nature and specific embodiments of the present invention, the scope is now particularly pointed out in the appended claims.

We claim: 1. A dye having the structure:

OH COOH wherein each X is a substituent group attached to the benzene nucleus independently selected from the class consisting of C to C alkyl, chloro, bromo, fiuoro, carbacyl having up to 6 carbon atoms, alkoxy containing 1-4 carbon atoms, trifluoromethyl, benzoylamino, and 2,3- benz-; R is a substituent group attached to the benzene nucleus selected from the group consisting of hydrogen 6. A dye composition which is 2,5-diethoxy-4-benzoylaminobenzeneazo-gamma-resorcylic acid.

7. A dye composition which is 2,5-dimethoxy-benzeneazo-gamma-resorcylic acid.

8. A dye composition which is 3-methylbenzeneazogamma-resorcylic ,acid.

9. A dye composition which is 4-trifluoromethylbenzeneazo-gamma-resorcylic acid.

10. A dye composition which is naphthaleneazogamma-resorcylic acid.

References Cited by the Examiner UNITED STATES PATENTS 431,297 7/1890 Walter 260207 528,965 11/1894 Muhlert 260-207 2,302,955 11/1942 Raiziss et al 260-196 2,516,303 7/1950 Dickey 260-496 X 2,717,823 9/1955 Lowe 260205 X 2,759,921 8/1956 Schmid et a1 260205 X 2,867,494 1/ 1959 Streck 8-42 2,877,219 3/1959 Ueda et a1. 260196 2,938,814 7/1959 Streck 8-42 CHARLES B. PARKER, Primary Examiner. 

1. A DYE HAVING THE STRUCTURE:
 10. A DYE COMPOSITION WHICH IS NAPHTHALENEAZOGAMMA-RESORCYCLIC ACID. 